must worsen
Regular verb: worsen - worsened- worsened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must worsen
you must worsen
she must worsen
we must worsen
you must worsen
they must worsen 	I must be worsening
you must be worsening
she must be worsening
we must be worsening
you must be worsening
they must be worsening	I must have worsened
you must have worsened
she must have worsened
we must have worsened
you must have worsened
they must have worsened	I must have been worsening
you must have been worsening
she must have been worsening
we must have been worsening
you must have been worsening
they must have been worsening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't worsen
you mustn't worsen
she mustn't worsen
we mustn't worsen
you mustn't worsen
they mustn't worsen 	I mustn't be worsening
you mustn't be worsening
she mustn't be worsening
we mustn't be worsening
you mustn't be worsening
they mustn't be worsening	I mustn't have worsened
you mustn't have worsened
she mustn't have worsened
we mustn't have worsened
you mustn't have worsened
they mustn't have worsened	I mustn't have been worsening
you mustn't have been worsening
she mustn't have been worsening
we mustn't have been worsening
you mustn't have been worsening
they mustn't have been worsening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I worsen?
must you worsen?
must she worsen?
must we worsen?
must you worsen?
must they worsen? 	must I be worsening?
must you be worsening?
must she be worsening?
must we be worsening?
must you be worsening?
must they be worsening? 	must I have worsened?
must you have worsened?
must she have worsened?
must we have worsened?
must you have worsened?
must they have worsened? 	must I have been worsening?
must you have been worsening?
must she have been worsening?
must we have been worsening?
must you have been worsening?
must they have been worsening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I worsen?
mustn't you worsen?
mustn't she worsen?
mustn't we worsen?
mustn't you worsen?
mustn't they worsen? 	mustn't I be worsening?
mustn't you be worsening?
mustn't she be worsening?
mustn't we be worsening?
mustn't you be worsening?
mustn't they be worsening? 	mustn't I have worsened?
mustn't you have worsened?
mustn't she have worsened?
mustn't we have worsened?
mustn't you have worsened?
mustn't they have worsened? 	mustn't I have been worsening?
mustn't you have been worsening?
mustn't she have been worsening?
mustn't we have been worsening?
mustn't you have been worsening?
mustn't they have been worsening?